Widgetlords Controller - Node-Red, Raspberry Pi Controller Build

[MaddyP]

Hello All!

Thought it would be best to separate my aquarium controller build from my tank build thread:

https://www.reef2reef.com/threads/maddyps-12g-long-node-red-nano-build.549459/
So, a little background before we get into specifics. I had this crazy idea during my last move to try something out of the ordinary. I wanted a small tank but I didn't want any visible overflow...and I wanted a sump for equipment. Yeah, this means the plumbing would need to go in the bottom of the tank making it the perfect recipe for disaster!

But could it work?

Ultimately, I decided there was a possibility it could work if I approached the challenge from an automation perspective (my build thread documents all the different ideas I went through before landing on one that might be possible). To minimize the potential for disaster and implement the best control possible, a PLC would be needed to maintain the fine balance this system would require. So I went to AutomationDirect.com and bought a PLC setup with a Raspberry PI 3+ to handle graphical display.

Communication between the PLC/Raspi and my lack of understanding ladder programming lead me away from the PLC to something in between. Widgetlords Electronics offers a line of Node-Red supported Raspberry Pi interface modules which are designed for the automation industry. These allowed a simple way to interface inputs/outputs/relays with a Raspberry Pi through supported Node-Red nodes.

https://widgetlords.com/collections/pi-spi-din-series

After receiving some test boards from Widgetlords and starting development, I received an offer to transition into my companies IT organization. This required more time/travel/training than I anticipated so the project/tank sat untouched for nearly a year. Now that my wife is working from home, she has motivated me to pick this project back up. :) And since I've had nearly a year to think through, process, and research I have much more confidence in moving forward.

This thread will document my efforts to complete a controller utilizing a Raspberry Pi 4, Widgetlords interface boards, and various industry-level components.

 

[MaddyP]

Before ordering all the boards for this build, I did verify the PID loop would keep levels stable utilizing these boards and the modulating ball valve. After several days of successful tests we are moving forward! The setup is messy but I was able to confirm the design idea works as expected.

 

[MaddyP]

And all the boards have arrived to put together the bones of the controller!

Although it isn't the smallest controller, there is a lot of control packed into this package. It is also expandable down the line by simply plugging in new boards. As it stand it's about 16" long, 6" wide, and 3" tall including DIN rail.

This setup includes RS485, (2) digital inputs, (6) relay outputs, (6) analog outputs, (18) analog inputs, pH probe input, orp probe input, and temp input. All with supported Node-Red nodes. Power comes through the main board (24V) and runs through all sub-boards.

 

[MaddyP]

New Raspberry Pi4 4Gb! This will be running Raspbian Buster Lite to limit unneeded packages/graphical interface. Once Node-Red is up and running all development will be done through there.

Perform headless install and setup by including "ssh" file (with no extension) on the boot partition...

And SSH into the Pi via PuTTY to complete configuration.

And we're in...

Make sure all packages are updated:

sudo apt full-upgrade

Then install Node-Red:

bash <(curl -sL https://raw.githubusercontent.com/node-red/linux-installers/master/deb/update-nodejs-and-nodered)

Enable autostart on boot for Node-Red:

sudo systemctl enable nodered.service

Reboot Pi and verify Node-Red starts up automatically...bingo!

I also set up my wifi network and enabled I2C/SPI via raspi-config:

sudo raspi-config

 

[MaddyP]

Now to install the needed packages to utilize Widgetlords interface boards. Instructions can be found here...

https://widgetlords.com/pages/getting-started-with-pi-spi-libraries
Download the libwidgetlords package from latest release:

wget https://github.com/widgetlords/libwidgetlords/releases/download/v2.1.0/libwidgetlords_2.1.0_armhf.deb

And install package:

sudo dpkg -i libwidgetlords_2.1.0_armhf.deb

Set appropriate overlay in /boot/config.txt:

sudo nano /boot/config.txt

And to make use of the battery-backed real time clock, follow these instructions:

https://cdn.shopify.com/s/files/1/0..._DIN_RTC_Instructions.pdf?5124813895305158384
That should do it for the Widgetlords library. I am not a Raspberry Pi expert so please let me know if I've made any mistakes...

 

[MaddyP]

Next will be installing the additional Node-Red nodes I will use. I'm sure more will be added in time, but for now these will get me going.

node-red-contrib-i2c	To interface with Ezo boards (pH, ORP, Temp).
node-red-contrib-os	To access Pi system data (CPU, Memory, Firmware).
node-red-contrib-widgetlords	To control Widgetlords boards (inputs/outputs/relays).
node-red-node-pidcontrol	To control modulating ball valve in relation to sensor.
node-red-node-sqlite	To manage on-board sqlite database for sensor data.
node-red-dashboard	To support graphical interface.

These can all be installed from Node-Red in "Manage Palette".

All nodes should install without issue, with the exception of node-red-contrib-i2c. This will error due to an issue with the Node.js version. To get around this error, navigate to the node_modules directory:

cd .node-red/node_modules

And install i2c-bus:

npm install i2c-bus

Navigate back to ~/.node-red:

cd .node-red

And install node-red-contrib-i2c directly from NPM:

npm install --unsafe-perm https://github.com/nielsnl68/node-red-contrib-i2c

 

[MaddyP]

Setup is complete and Pi 4 has been mounted on the assembly!

 

[pelican]

Awesome. Was following this on your other thread. Looking forward to seeing where you take this!

 

[MaddyP]

Quick and dirty system stats. I'll clean this up later.

Flow:

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[MaddyP]

Since the purpose of a controller is to control things, this thread would only be half complete without a BOM. I'll do my best to include all the components which will interface with the controller and explain their purpose in my build.

Part	Model	Interface	Purpose	Images
Raspberry Pi 4	Raspberry Pi 4 GB Ram		Graphical interface and control of interface boards.
Main Interface Board	Widgetlords PI-SPI-DIN-2x4MIO		Main interface board.
Analog Input Module	Widgetlords SDAFE	(2) Software Defined Analog Input	Analog inputs for sensors/valves.
Analog Input Board	Widgetlords PI-SPI-DIN-8AI	(8) 0-20mA analog inputs.	Analog inputs for sensors/valves.
Analog Input Board	Widgetlords PI-SPI-DIN-8AI	(8) 0-5V analog inputs.	Analog inputs for current sensors.
Relay Output Board	Widgetlords PI-SPI-DIN-4KO	(4) Relay outputs.	Relays for 110V outlets.
Analog Output Board	Widgetlords PI-SPI-DIN-4AO	(4) Analog Outputs.	Analog outputs for actuators/pump.
Tentacle T3 Board	Whitebox Labs TEN-T3	(5) Ezo devices	Probes inputs (pH, ORP, temp).
Ezo pH Circuit	Atlas Scientific EZO-ph	pH probe.	pH probe.
Ezo ORP Circuit	Atlas Scientific EZO-ORP	ORP probe.	ORP probe.
Ezo RTD Temp Circuit	Atlas Scientific EZO-RTD	Temp probe.	Temp probe.
Actuator	HSH Flo TC02-T	0-20mA Input 0-20mA Output	Actuator will control 3-way ball valve for modulating flow between two returns.
Actuator	HSH Flo TC02-T	0-10V Input 0-10V Output	Actuator will control ball valve for modulating drain.
Ultrasonic sensor	Automation Direct UK6A-D2-0E	4-20mA Input	Sensor to monitor sump water level for PID control of actuator.
Dosing Pump	APT Instruments SP100-004	12V Relay.	Dosing elements.
Heater	Cobalt Neotherm	110V Relay	Heating tank.
Power Strip	TPLink Kasa HS300	Wifi	Control 110v devices.
Temp Probes	Atlas Scientific PT-1000	BNC Connector	Measure temperature.
LED Drivers	ALab Tech 5ch 48V	Wifi	Controls light fixture

 

[FischAutoTechGarten]

So, have you completely eliminated the Productivity 1000 PLC from your setup?

If so, then your setup is similar to mine, except I prefer the i2c expansion boards from NCD.
8ch relay :

4 ch A-D

I'll be watching your project closely. Thanks for posting details.

 

[MaddyP]

So, have you completely eliminated the Productivity 1000 PLC from your setup?

If so, then your setup is similar to mine, except I prefer the i2c expansion boards from NCD.
8ch relay :

4 ch A-D

I'll be watching your project closely. Thanks for posting details.

I still like the PLC idea but taking the time to develop the ladder code was a little more than I wanted to get into. Also, consolidating this project into Node-Red with plug-and-play boards makes this project easier for others to replicate.

The relays boards I chose wouldn’t be applicable for larger tank as the rating at 110V is about 60 watts. But I can’t imagine, aside from my light, any of the equipment will consume more than 60W.

 

[kyleinpdx]

I still like the PLC idea but taking the time to develop the ladder code was a little more than I wanted to get into. Also, consolidating this project into Node-Red with plug-and-play boards makes this project easier for others to replicate.

The relays boards I chose wouldn’t be applicable for larger tank as the rating at 110V is about 60 watts. But I can’t imagine, aside from my light, any of the equipment will consume more than 60W.

Out of curiosity, with that wattage restriction, how are you handling temp control? Or are you using a heater smaller than the 60w of headroom you've got?

 

[MaddyP]

Out of curiosity, with that wattage restriction, how are you handling temp control? Or are you using a heater smaller than the 60w of headroom you've got?

I'll be using (2) 25W or (2) 50W Cobalt Neotherm heaters. Considering this will be supporting a 12G tank in Southern California, I don't expect the need to be more than a total of 60-100W.

 

[kyleinpdx]

I'll be using (2) 25W or (2) 50W Cobalt Neotherm heaters. Considering this will be supporting a 12G tank in Southern California, I don't expect the need to be more than a total of 60-100W.

Roger that. I was assuming something along those lines. Keep up the good work, I've been following this thread. I'm not as savvy with PLC's and automation as I could be, but my pops was a controls engineer for decades, working some cool projects including a now defunct nuclear power plant and many of the municipal waste water treatment centers around where I'm from. Its exciting to see someone bringing that to the aquarium controller game.

 

[MaddyP]

Roger that. I was assuming something along those lines. Keep up the good work, I've been following this thread. I'm not as savvy with PLC's and automation as I could be, but my pops was a controls engineer for decades, working some cool projects including a now defunct nuclear power plant and many of the municipal waste water treatment centers around where I'm from. Its exciting to see someone bringing that to the aquarium controller game.

Glad to hear you're excited, this is all new for me. I've not worked with this level of automation before, but part of the fun is the adventure! :)

 

[MaddyP]

Out of curiosity, with that wattage restriction, how are you handling temp control? Or are you using a heater smaller than the 60w of headroom you've got?

Another thought...if GHL would get around to releasing their Profilux Temp Control 2 I would consider it for this small tank...

https://www.aquariumcomputer.com/products/ghl-cooling-technology/profilux-temperature-control2/

 

[MaddyP]

Updated instructions for enabling real time clock as my initial instructions were incomplete...

 

[kyleinpdx]

Another thought...if GHL would get around to releasing their Profilux Temp Control 2 I would consider it for this small tank...

https://www.aquariumcomputer.com/products/ghl-cooling-technology/profilux-temperature-control2/

Oh man! Thanks for that link, I've havent seen that yet but seriously, just last night I was lying in bed thinking about starting a small cold water tank as I live an hour or two away from the pacific and could collect pretty easily. I didnt want to bother with a 1/4 or 1/3hp chiller so I was thinking through using peltiers! I've used them to cool some stupid overclocked PC's way back in the day. My biggest hurdle is finding a reasonably priced heat exchanger that wont get destroyed by the saltwater.

 

[MaddyP]

Oh man! Thanks for that link, I've havent seen that yet but seriously, just last night I was lying in bed thinking about starting a small cold water tank as I live an hour or two away from the pacific and could collect pretty easily. I didnt want to bother with a 1/4 or 1/3hp chiller so I was thinking through using peltiers! I've used them to cool some stupid overclocked PC's way back in the day. My biggest hurdle is finding a reasonably priced heat exchanger that wont get get destroyed by the saltwater.

If you decide to follow through on this project, I will most definitely follow closely!